Key dates in the revolt in Yemen

- January 27: Inspired by revolts in Tunisia and Egypt, Yemenis rally to demand the ouster of President Ali Abdullah Saleh.

- February 3: Tens of thousands of protesters stage a "day of rage." Saleh loyalists hold counter-demonstration.

- March 18: Regime loyalists fire on demonstrators in Sanaa, killing 52. Saleh declares state of emergency.

- March 23: Saleh says he is willing to step down at end of 2011.

- April 4-6: At least 25 die in clashes between security forces and protesters.

- April 8: Saleh rejects a Gulf Cooperation Council (GCC) plan for his departure, which would have seen an opposition-led national unity government.

- May 22: Saleh refuses to sign a new plan under which he would quit 30 days after creation of a national unity government. He warns of "civil war." The Gulf countries suspend mediation efforts.

- May 23-24: Clashes between security forces and tribesmen kill at least 44 people near the Sanaa home of powerful tribal chief Sheikh Sadiq al-Ahmar, who pledged support for the anti-regime protests in March.

- May 25: US President Barack Obama calls on Saleh to hand over power immediately.

- May 28: Three French nationals working in Yemen reported missing in Hadramawt province in the southeast.

- May 29: More than 200 gunmen believed to be linked to Al-Qaeda take control of the south Yemen city of Zinjibar, capital of Abyan province, after fighting with security forces that leaves 23 people dead.

- May 30: Forces loyal to Saleh disperse sit-in in Taez, Yemen's second-largest city.

- May 31: An opposition spokesman says Gulf mediation in Yemen is "over" because Saleh persistently refuses to sign a deal on transition of power.

- June 1: Fighting between alleged Al-Qaeda militants and security forces continues in Zinjibar, with at least 41 soldiers and civilians being killed there since May 29.
Fighting also rages between tribesmen in the streets of Sanaa's Al-Hassaba neighbourhood, bastion of Ahmar.

- June 2: A third night of clashes between security forces and Ahmar's tribesmen in Al-Hassaba, where 63 have been killed in two days.

- June 3: Saleh wounded along with his premier and other officials as shells strike a mosque in the presidential palace compound. Four Republican Guard officers killed.
Fighting spreads to the south of Sanaa.